The present disclosure relates to an inverter, and more particularly, to a communication method in an inverter system including a plurality of inverts.
In modern industries, most of driving devices include motors, and inverters are required to precisely control the motors. Additionally, a Programmable Logic Controller (PLC) is currently used as a method of controlling a plurality of inverters.
Moreover, motors are indispensable across all industries, and therefore, the need for inverters is increased. As devices for efficiently controlling motors, inverters reduce power consumption of motors and increase their energy efficiency.
Recently, linking and operating a plurality of motors become more frequent, and accordingly, a linking operation by sharing information on a plurality of inverters becomes more frequent.
As mentioned above, when inverters are in linking operations, a plurality of inverters need to exchange information data or command data with each other in order to smoothly drive motors.
FIG. 1 is a schematic view illustrating a configuration of a related art inverter system.
Referring to FIG. 1, an inverter communication system includes a communication device 10, a plurality of inverters 20-1, 20-2, 20-3, and 20-4, and a plurality of motors 30-1, 30-2, 30-3, and 30-4 driven by controls of the inverters 20-1, 20-2, 20-3, and 20-4.
The communication device 10 operates as a communication master for communication between the plurality of inverters 20-1, 20-2, 20-3, and 20-4.
The plurality of inverters 20-1, 20-2, 20-3, and 20-4 serve as a slave device to perform a communication with the communication device 10 through a communication line. Additionally, the plurality of inverters 20-1, 20-2, 20-3, and 20-4 and the communication device 10 exchange mutual data with each other through the communication line.
The communication device 10 collects data through communication with each of the plurality of inverters 20-1, 20-2, 20-3, and 20-4, and controls each of the plurality of inverters 20-1, 20-2, 20-3, and 20-4 by using the collected data.
In the same manner, the communication device 10 may efficiently control the plurality of inverters 20-1, 20-2, 20-3, and 20-4 in a complex system or a large scale system.
However, if there are a plurality of motors 30-1, 30-2, 30-3, and 30-4 (for example, two to five motors), the structure of the inverter system becomes complex. Accordingly, operators may make errors easily.
Additionally, since the inverter system includes the additional communication device 10, system building costs are increased.
Additionally, since the communication device 10 needs to be installed in a different place than a place where the plurality of inverters 20-1, 20-2, 20-3, and 20-4 are installed, installation space may be wasted.
Moreover, since the inverters 20-1, 20-2, 20-3, and 20-4 communicate with the communication device 10 that operates as the master, a communication line used for communicating with the communication device 10 becomes longer. Therefore, errors may occur in communication data according to external environmental conditions such as noise.